In which control valve energy consumption reduces as load decreases?
A. conventional direction control valve
B. proportional direction control valve
C. both a and b
D. none of the above
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Which of the following is a characteristic of servo valve?
A. open loop system
B. closed loop system
C. less contamination
D. all the above
What is the function of a pressure switch or relay?
A. pressure switch is used to start a motor
B. pressure switch is used to stop a motor
C. pressure switch is used to deenergize a solenoid
D. all the above
A unloading circuit composed of three-position four-way directional control valve requires that the two chambers of the hydraulic cylinder are blocked when the hydraulic cylinder stops. What type of center function of the directional valve should be selected ? ()
A. “M”
B. “Y”
C. “P”
D. “O”
What does the numbers in 4/2 valve mean?
A. 4 positions and 2 ways
B. 4 ways and 2 positions
C. none of the above